Efest 18650 3100mAh (Black)



Official specifications:

• Efest 18650 3100mAh 3.7V Protected (Nipple)
• Nominal Capacity: 3100mAh (0.2C, 2.50V discharge)
• Minimum Capacity: 2950mAh(0.2C, 2.50V discharge)
• Charging Voltage: 4.2 ±0.05 V
• Nominal Voltage:3.6V
• Charging Method CC-CV (constant voltage with limited current)

This battery uses a unusual construction with the protection mounted at the + pole. The maximum current from this battery is not very high, probably due to the unusual protection placement.





















Protection trip current is to low to show in the chart.





Conclusion

This battery uses a very good cell and is one of the shortest 3100mAh protected batteries, but due to the low current limit it will not work in all lights (The problem is XM-L lights).



Notes and links

The batteries was supplied by Efest for review.

How is the test done and how to read the charts
How is a protected LiIon battery constructed
More about button top and flat top batteries